The current drawn by a motor is indicative of the operating condition of the motor. If the motor draws too little current, the power generated by the motor may be insufficient to operate an apparatus in which the motor is installed, for example, to cool the air inside a refrigerator. If, on the other hand, the motor draws too much current, the high level of current may cause excessive wear on the motor, reducing the life span of the apparatus, or even cause immediate damage to the motor.
Monitoring devices have been utilized with motors in order to sense the current drawn by the motor over a period of time and to respond to malfunctions detected in the motor based on the current sensed. In particular, some conventional monitoring devices compare the sensed current to a fixed threshold value in order to detect situations in which the motor is drawing too little current or too much current.